Spontaneous cerebrospinal fluid otorrhea from tegmen tympani defect caused by an arachnoid cyst - A case report

Adult-onset cerebrospinal fluid (CSF) otorrhea is usually associated with a herniation of brain tissue, or meninges as a consequence of surgery or temporal bone trauma. Spontaneous CSF leakage is a rare condition. Spontaneous CSF leakage from the tegmen tympani caused by an arachnoid cyst has not been reported in the literature. We present a unique case in which an infra-temporal arachnoid cyst eroded the tegmen tympani that caused conductive hearing loss, CSF otorrhea, and repealed meningitis. Surgical management involved marsupilization of cyst and sealing the dura fistula while preserving ossicles through a middle cranial fossa approach.